By Greg Allan, tradesman and creator of Data First Coaching
Why do so many waterproofing business owners get their safety duties wrong?
A waterproofing business often works right at the edges of someone else's site: a bathroom mid-renovation, a balcony three storeys up, a basement with no natural light, a roof deck waiting on a tiler. Because the builder usually runs the main site, many waterproofers assume health and safety is someone else's job once the membrane goes on. That assumption is a common gap, and it costs far more to fix after a fall, a chemical exposure or an inspection goes wrong than it would have cost to sort out before the job started. None of that comes from a bad tradesperson; it comes from duties nobody wrote down.
Who is the PCBU on your waterproofing job?
Under the Health and Safety at Work Act 2015, you are most likely a PCBU, a 'person conducting a business or undertaking', the moment you run or work in your waterproofing business, whether you are a sole operator or employ a crew. According to Introduction to the Health and Safety at Work Act 2015, WorkSafe New Zealand says “A PCBU must ensure, so far as is reasonably practicable, the health and safety of workers, and that other persons are not put at risk by its work.” That is called the primary duty of care.
On most jobs you are not the only PCBU. The builder managing the site, the tiler working after you, and you as the waterproofer can each hold a duty at once. Appendix C: Health and Safety at Work Act duties explains that PCBUs with overlapping duties must, so far as is reasonably practicable, consult, cooperate and coordinate with each other, and must give workers a genuine say in health and safety matters that affect them. Handing your crew a membrane job and assuming the builder has it covered does not meet that duty.
What are your duties around height, membranes and chemicals?
Your two biggest risk areas as a waterproofer are working at height on balconies, roof decks and upper floor wet areas, and handling the chemicals in primers, membranes and solvents, and WorkSafe expects both to be eliminated or minimised, so far as is reasonably practicable, before the job starts.
On falls, Working at height in New Zealand states that “WorkSafe is the main regulator responsible for administering and enforcing HSWA”, and that if there is potential for a fall from any height, your general duty of care requires reasonably practicable steps to prevent it. WorkSafe's own guidance on roof work sets out the order to work through: “eliminate the chances of a fall by doing as much of the preparation work as possible on the ground”, before isolating the remaining risk with scaffolding or edge protection, as set out in Be safe working on roofs. Where a job needs scaffolding, Scaffolding in New Zealand explains that PCBUs must manage risks from falling objects and working under raised loads, and that scaffolders need a certificate of competence issued by SARNZ under WorkSafe's delegated authority.
On chemicals, membrane primers, solvents and two-pack systems are classed as hazardous substances under the Hazardous Substances and New Organisms Act 1996. Managing your hazardous substances says containers in your workplace, including anything decanted on site, must stay labelled, and Regulations, legal requirements and rights says a PCBU must identify the hazard, eliminate or minimise exposure so far as is reasonably practicable, and provide the training, instruction and PPE your crew needs to work with it.
Do you need to be a Licensed Building Practitioner to waterproof in New Zealand?
Waterproofing to a home's weathertightness, meaning membranes to a balcony or roof deck and waterproof coatings exposed to the weather, is classed as restricted building work, so this specific work must be designed and carried out by a Licensed Building Practitioner, not just supervised by one.
Restricted building work describes this as work to a home's “external moisture management systems”, and names waterproof coating to walls and roofs exposed to airborne moisture, and waterproof membranes to deck and balcony areas, specifically. It states plainly: “You must use Licensed Building Practitioners (LBPs) to design and carry out this work.” For a waterproofer, that sits alongside your health and safety duties rather than replacing them: a flood test and a certificate show the membrane meets standard, while your safety records show the crew that did the work was protected while doing it. A remedial job on a leaking balcony, or insurance work after a defect claim, can carry both obligations at once, which is where owners most often lose track.
What does this mean for your paperwork and records?
Every duty above turns into a record: who you told about a hazard, what training an apprentice had before handling a membrane, which flood test and certificate belongs to which bathroom or balcony, which site induction a crew member signed before going up on a roof deck. Memory does not hold that. Your own job data does.
A waterproofing business juggles several live jobs at once, a wet area for one builder, a basement rectification for another, remedial work under warranty for a third, and the paperwork trail for each is different. Working from memory at the end of a busy month, when a WorkSafe visit or an insurance claim asks for proof, is where the gaps appear. A data first approach starts from the job itself: the induction, the hazard notice, the chemical label, the cure time, the flood test certificate, all tied to that specific job as it happens, not pieced together afterwards.
This is where AI agents can carry weight for a waterproofer. An AI agent is software that does a job the way you would, using your own wording, your own checklist and your own rules, so a membrane job cannot be marked complete until the right record exists against it. AI agents built this way can hold your crew to the induction and consultation duties WorkSafe expects before a job starts, while another keeps the certificate, flood test result and hazardous substance record together against the job file, ready the day someone asks, whether that is a builder chasing a warranty claim or an inspector asking a question.
This is general information, not legal, tax or employment advice. Check your own situation with the body named here or a qualified adviser.
Where can you check the current rules?
- Introduction to the Health and Safety at Work Act 2015: what a PCBU is and the primary duty of care, from WorkSafe New Zealand.
- Appendix C: Health and Safety at Work Act duties: overlapping PCBU duties and worker engagement.
- Restricted building work: when waterproofing needs a Licensed Building Practitioner.
- Managing your hazardous substances: labelling and handling membrane chemicals, primers and solvents.
- Regulations, legal requirements and rights: exposure, training and PPE duties.
- Working at height in New Zealand: fall risk duties on balconies and roof decks.
- Be safe working on roofs: WorkSafe's order of steps for roof fall prevention.
- Scaffolding in New Zealand: scaffolding duties and certificates of competence.
How does Data First Coaching approach this?
Data First Coaching does not start by asking a waterproofer to recite a safety policy from memory. It starts with the Trade Business Intelligence reading the owner's own job data, which jobs carried height work, which carried hazardous substances, which counted as restricted building work, and checks that against what the records actually show. Often the real gap is not the duty itself but where in the job it gets missed, an induction skipped on a quiet Monday, a certificate filed against the wrong address. Greg Allan built Data First Coaching from running his own trade business, and the Academy works through how an owner closes that gap, with members, inside the Academy, because the Trade Business Intelligence is powered by every member who joins it.
